Modular lighting refers to modules that can be assembled in order to obtain large lighting devices of various sizes and shapes. Each lighting module has several light elements, e.g. RGB LEDs. In addition to the flexibility in adapting the size and shape of such modular lighting applications, e.g. to the available space where the modular lighting application is to be installed or due to other reasons, such modular lighting applications may be used to visualize lighting patterns, such as still or moving images or light effects, on a screen that may have a size and a shape that in general deviates from standard rectangular liquid crystal display (LCD) devices. Particularly two-dimensional lighting modules are typically referred to as lighting tiles, or simply tiles. Such a lighting module may have various polygonal shapes, such as for example a square, triangle or pentagon shape. The lighting modules are not limited to two-dimensional shapes but may have a three-dimensional shape, such as a cube or a pyramid.
WO 2007/063487 discloses a prior art method for controlling a lighting system. The lighting system is built up from a plurality of lighting modules, which are interconnectable to form an array of a desired shape. The system includes a controlling device that is connected to one of the lighting modules in an array. The controlling device provides the array with lighting data, and when the lighting modules are correctly addressed the array displays a desired lighting pattern, such as an image, video, light effect or the like, on basis of the lighting data. Such a lighting system can be used in many different applications, but is often mounted on a wall, a ceiling, or a free standing holder.
It is desired that the lighting system is easy to mount and start to use. This is the case with the system disclosed in WO 2007/063487. The lighting modules are arbitrarily interconnectable by mechanical as well as electrical connections, such as communication units, arranged at their sides. This freedom of connection, however, raises demands on how to communicate lighting data throughout the array of lighting modules such that each module receives the correct data as well as displays the data correctly. According to WO 2007/063487 there is performed a learning procedure for defining a lighting module arrangement and a communication network for communication between the controlling device and the lighting modules. The controlling device sends a token to the connected lighting module. The token is then forwarded from module to module, while ensuring that all lighting modules are visited by the token. Concurrently, geometric information about how the lighting modules are arranged in relation to each other is obtained and reported back to the controlling device. Thereby information about the structure is acquired.
Further, as regards the addressing, initially the lighting modules have no address. The lighting modules are each assigned an address when the token first arrives there. After each assignment the address is updated, and the updated address is forwarded with the token to next module, to ensure that the same address is not provided to two different modules.
This method of gaining knowledge about the structure of the array and providing the modules with individual addresses is very flexible and accurate, but it is rather complex and requires a rather competent controlling device. For some applications a more simple solution would have been sufficient.